# -*- coding: utf-8 -*-
import cv2 as cv
import numpy as np

img = cv.imread("photos/dog.jpg")
cv.imshow("Dog", img)


blank = np.zeros(img.shape[:2], dtype="uint8")
cv.imshow("Blank", blank)

(height, width) = img.shape[:2]

mask = cv.circle(blank, (width//2, height//2), 100, 255, -1)
cv.imshow("mask", mask)

masked = cv.bitwise_and(img, img, mask=mask)
cv.imshow("masked image", masked)


cv.waitKey(0)